Barak RavidAdd Axios as your preferred source tosee more of our stories on Google.Crude oil tankers, bulk carriers and vessels sit anchored around Qaboos Port in June in Muscat, Oman. Photo: Elke Scholiers/Getty ImagesIran's military fired at least two missiles at commercial ships transiting the Strait of Hormuz on Monday night, two U.S. officials tell Axios.Why it matters: The reported attacks threaten to unravel a memorandum of understanding signed less than three weeks ago under which Iran agreed to halt attacks in the Strait of Hormuz.And they come after one-week agreement between the U.S. and Iran on halting attacks in the strait expired.The U.S. is likely to retaliate with strikes against Iranian targets. Driving the news: The United Kingdom Maritime Trade Operations said Monday it received a report from a tanker traveling south near Oman in the Strait of Hormuz coast that was struck by an unknown projectile, causing a fire.A U.S. official said a second commercial vessel was struck by an Iranian missile.Both vessels suffered significant damage, but no casualties, the U.S. official said. State of play: A round of indirect talks between the U.S. and Iran in Doha last week ended without much progress on the issue of the Strait of Hormuz.Editor's note: This is a breaking news story. Please check back for updates.